Heat across three oceans
Global ocean temperatures are on track to break the all-time record this year, scientists warned this week. New data from climate monitoring agencies shows average sea surface temperatures running above the previous record, which was set in 2023.
Marine heat waves are spreading across the Atlantic, Pacific and Indian Oceans. Some regions have seen temperatures several degrees above normal for weeks at a time, with the Caribbean, the Mediterranean and parts of the western Pacific among the hardest hit.
What warmer seas mean for weather and wildlife
The warmth is already having visible effects. Coral reefs in several regions have suffered new bleaching events, and fish populations are shifting toward cooler waters, disrupting fishing communities. Warmer oceans also add energy to storms, and forecasters have noted that this year's hurricane and typhoon seasons are running above average.
Marine heat waves can also kill kelp forests and seagrass meadows, which provide food and shelter for countless species. Scientists said the current events bear the fingerprints of long-term warming driven by greenhouse gas emissions.
Why this record matters
The record heat comes even as the Pacific shifts away from El Nino conditions, which normally add extra warmth to global temperatures. That detail matters, scientists said, because it shows the oceans are now warming mostly from the build-up of heat-trapping gases, not from natural cycles.
The findings add urgency to calls for stronger emissions cuts ahead of upcoming international climate talks. Researchers noted that the ocean absorbs more than 90% of the excess heat from climate change, and its rising temperature is one of the clearest signals that the planet is warming.
Coastal communities are already adapting. Some fishing ports are changing their seasons, and tour operators that depend on coral reefs are watching the bleaching with worry. Scientists said the coming months will show whether the ocean cools again or pushes even higher.